CN104385920B - Realization method of pointer type virtual instrument panel - Google Patents

Abstract

The invention discloses a realization method of a pointer type virtual instrument panel. The realization method comprises the following steps: an equipment context is built; a dial background is loaded; a memory context is duplicated, and the dial background serves as a canvas; a pointer picture is loaded; the size of the pointer picture is obtained; a pointer rotating center is set; after a pointer rotates an angle alpha, the rasterization treatment is performed with a coordinate as a rotating center according to step distance; each small rectangle coordinate is obtained; the pointer rotating the angle alpha is drawn in one of the memory contexts; the picture in the corresponding position of the memory context is duplicated in the equipment context for displaying; after the angle alpha is changed, the pointer is drawn in the memory context again; the last pointer display content in the equipment context is erased by the corresponding background picture in the other one of the memory contexts according to the pre-change rectangle coordinate of the angle alpha; and the picture in the corresponding position of the memory context is duplicated in the equipment context for displaying according to the post-change rectangle coordinate of the angle alpha.

Description

A kind of implementation method of pointer virtual meter panel

Technical field

The invention belongs to motor vehicle instrument disk technology field, be specifically related to a kind of realization side of pointer virtual meter panel Method.

Background technology

At present, modal instrument board great majority employing moving-coil or moving-magnetic type analogue instrument, step motor type digital instrument Mode is carried out information demonstration, and along with computer and lcd technology further develop, some equipment start progressively to adopt liquid Brilliant screen carries out man-machine interaction, and instrument board also becomes more and more beautiful thus, and function is more and more, from practicality start to move towards fashion, Dazzling, finally complete perfect adaptation practical and fashion.

In order not change operator's use habit, although upgrading to liquid crystal display gradually, the instrument board of a lot of equipment shows, But also will on liquid crystal display, Reality simulation instrument show as the parameter such as engine speed, the speed of a motor vehicle, this demand is to product Realization bring a lot of problems:

First, when indicator rotates, need the inertial elements such as analogsimulation instrument acceleration, deceleration, show and want continuously, can not a step One step is beated;

Secondly, it is high that refreshing frequency is wanted, and generally will reach Millisecond, because refresh rate is fast, when background redraws, easily causes Screen flicker.

For above problem, a lot of producers adopt double buffering technology to eliminate the flicker problem of instrument display frame, and effect also Undesirable, the mode of employing double buffering, has only solved the efficiency such as backstage graphic plotting, complex figure calculating, but can not carry The high speed reading from buffer memory, along with screen and resolution ratio progressively become greatly, the virtual instrument quantity change of demonstration is many, the asking of flicker Topic just becomes fairly obvious. Because embedded device resource is more limited, some producer sacrifices hardware cost and solves software issue, Cause cost to increase.

Summary of the invention

The technical problem to be solved in the present invention is the realization of a kind of pointer virtual meter panel with following function of design Method: specific region is divided into several little square frames, when background redraws, only need to refreshes the square frame obtaining by calculating, Reduce and refresh area, can solve virtual dial plate flicker problem in real-time refresh process, improve dial plate display effect and hardware Service efficiency, reduces hardware cost.

For solving the problems of the technologies described above, the technical solution used in the present invention is:

An implementation method for pointer virtual meter panel, comprises the steps:

Step 101, set up a device context DC;

Step 102, loading dial plate background, and show on device context DC;

Step 103, copy two parts of memory context MEMDC1, MEMDC2, dial plate background is as painting canvas;

Step 104, loading indicator picture;

Step 105, obtain indicator image size, width w, length l, now indicator can represent to grow into l, wide is w's Rectangle;

Step 106, indicator pivot (X is set₀,Y₀)；

After step 107, indicator rotation alpha angle, with coordinate (X₀,Y₀) be pivot, carry out rasterizing place with step distance Reason;

Step 108, calculate by geometry, obtain each little rectangular coordinates;

Step 109, in memory context MEMDC1, draw the indicator of rotation alpha angle;

Step 110, the rectangular coordinates obtaining according to step 108, relevant position image in memory context MEMDC1 is multiple System shows to device context DC;

Step 111, after angle [alpha] changes, in memory context MEMDC1, repaint indicator, and by how much Calculate new rectangular coordinates;

Step 112, change according to angle [alpha] before rectangular coordinates, with respective background image wipe in memory context MEMDC2 Last indicator displaying contents on device context DC, keeps background constant;

Step 113, according to angle [alpha] change after rectangular coordinates, by relevant position copying image in MEMDC1 to equipment Below on DC, show;

If step 114 angle [alpha] changes, repeating step 111～113.

Further: the concrete computational process of above-mentioned steps 108 is as follows:

Step 1, known indicator image size, i.e. width w and length l, anglec of rotation α, step-length step;

Step 2, according to anglec of rotation α, known straight slope k=tan (α)

System coordinates is moved to indicator pivot (X by step 3.₀,Y₀) can obtain asking middle line function

y′＝k*x′

Wherein: x ' is the abscissa in translate coordinate system, y ' is the ordinate in translate coordinate system

Step 4, in the time of 0≤α≤45, according to picture width w, two long limits can obtaining other indicator rectangle frame are parallel Line function equation:

$y_{01}^{\′}=k*x^{\′}-\frac{w}{2*\cos \left(\mathrm{\α}\right)}$

$y_{02}^{\′}=k*x^{\′}+\frac{w}{2*\cos \left(\mathrm{\α}\right)};$

Wherein: y '₀₁For the ordinate near x axial length limit, y '₀₂For the ordinate near y axial length limit.

Step 5, ask indicator image end points B0 point coordinates (x '_B0,y′_B0)

$x_{B0}^{\′}=l*cos\left(\mathrm{\α}\right)+\frac{w}{2}*sin\left(\mathrm{\α}\right)$

$y_{B0}^{\′}=l*\sin \left(\mathrm{\α}\right)-\frac{w}{2}*\cos \left(\mathrm{\α}\right)$

After step 6, vertical grid are processed, ask the grid coordinate that first rectangle (from right to left) upper left corner A0 orders (x "_A0, y″_A0)

$x_{A0}^{\′\′}=quotient\left(\frac{x_{B_0}^{\′}}{step}\right)$

$y_{A0}^{\′\′}=quotient\left(\frac{y_{B_0}^{\′}}{step}\right)-1$

Step 7, ask y '₀₂The coordinate of the intersection point C0 of extended line and first rectangle (x '_C0,y′_C0)

x′_C0＝(x′_A0+1)*step

$y_{C0}^{\′}=k*x_{C0}^{\′}+\frac{w}{2*\cos \left(\mathrm{\α}\right)}$

In step 8, grid coordinate, the grid coordinate of asking the lower right corner D0 of first rectangle to order

$x_{D0}^{\′\′}=quotient\left(\frac{x_{C_0}^{\′}}{step}\right)=x_{A0}^{\′\′}+1$

$y_{D0}^{\′\′}=quotient\left(\frac{y_{C_0}^{\′}}{step}\right)+1$

Step 9, the coordinate system of looking for novelty, i.e. linear equation in Grid Coordinate System

y″＝k*x″|c

Wherein: x " being the abscissa in Grid Coordinate System, y " is the ordinate in Grid Coordinate System

Will (x "_A0,y″_A0) substitution equation, try to achieve

c＝y″_A0-k*x″_A0

: y " k*x "+y "_A0-k*x″_A0

Simplify: y "=k* (x "-x "_A0)+y″_A0

Step 10, will (x ", the processing of y ") discretization, n point coordinates is

x″_An＝x″_A0-n

y″_An＝y″_A0-quotlent (k*n/0.99), 0.99 eliminates k conversion accuracy problem

Step 11, by α=45 substitution 4～10 steps, can obtain y direction grid limit quantity num, other anglecs of rotation Y direction grid quantity can not be greater than num, simplifies procedures operation time

num＝y″_D0-y″_A0

Step 12, calculate by above, draw first rectangular coordinates

Upper left corner coordinate: (x "_A0,y″_A0)

Lower right corner coordinate: (x "_D0，y″_D0)＝(x″_A0+1，y″_A0+num)

Step 13, other rectangular coordinates,

N rectangle upper left corner coordinate:

(x″_An，y″_An)＝(x″_A0-n，y″_A0-quotlent(k*n/0.99))

N rectangle lower right corner coordinate:

(x″_Dn，y″_Dn)＝(x″_An+1，y″_An+num)

Wherein n span: 0 < n≤x "_A0

Step 14, calculating above, be applicable to angular range (0≤α < 45), and as Fig. 6, indicator is near x axle, and rectangle frame is to erect length Shape is best, and (135≤α < 180), (180≤α < 225), (315≤α < 360) are also the same reasons; Other angle case, indicator Near y axle, rectangle frame is taking the wide shape of horizontal stroke as best, as Fig. 7.

Step 15, according to trigonometric function characteristic, can calculate the coordinate of all angular ranges, specific as follows:

(1) first quartile

Angular range (0≤α < 45)

The 1st rectangle (x "_A0，y″_A0)，(x″_D0，y″_D0)}

N rectangle (x "_An，y″_An)，(x″_Dn，y″_Dn)}

Angular range (45≤α < 90), α=90-α

The 1st rectangle (y "_A0，x″_A0)，(y″_D0，x″_D0)}

N rectangle (y "_An，x″_An)，(y″_Dn，x″_Dn)}

(2) the second quadrant

Angular range (90≤α < 135), α=α-90

The 1st rectangle (y "_D0，x″_A0)，(-y″_A0，x″_D0)}

N rectangle (y "_Dn，x″_An)，(-y″_An，x″_Dn)}

Angular range (135≤α < 180), α=180-α

The 1st rectangle (x "_D0，y″_A0)，(-x″_A0，y″_D0)}

N rectangle (x "_Dn，y″_An)，(-x″_An，y″_Dn)}

(3) third quadrant

Angular range (180≤α < 225), α=α-180

The 1st rectangle (x "_D0，-y″_D0)，(-x″_A0，-y″_A0)}

N rectangle (x "_Dn，-y″_Dn)，(-x″_An，-y″_An)}

Angular range (225≤α < 270), α=270-α

The 1st rectangle (y "_D0，-x″_D0)，(-y″_A0，-x″_A0)}

N rectangle (y "_Dn，-x″_Dn)，(-y″_An，-x″_An)}

(4) fourth quadrant

Angular range (270≤α < 315), α=α-270

The 1st rectangle (y "_A0，-x″_D0)，(y″_D0，-x″_A0)}

N rectangle (y "_An，-x″_Dn)，(y″_Dn，-x″_An)}

Angular range (315≤α < 360), α=360-α

The 1st rectangle (x "_A0，-y″_D0)，(x″_D0，-y″_A0)}

N rectangle (x "_An，-y″_Dn)，(x″_Dn，y″_An)}

Step 16, above all quadrants coordinate are all with coordinate (X₀,Y₀) centered by, grid coordinate taking step as step-length, use In time, can revert to device coordinate or obtain device coordinate by grid matrix.

Advantage and good effect that the present invention has are: by adopting technique scheme, original large area is refreshed Region Segmentation becomes several little rectangles, according to the position of indicator rotation, and the region that a refreshed image changes, instead of whole district Territory, has improved efficiency greatly, and taking indicator figure image width 12 pixels, long 120 pixels, grid distance 10 pixels as example, refreshing efficiency can To improve 80%, be five times of original efficiency. Refresh after efficiency high jump, background redraw process flicker problem is resolved, indicator Procedure for displaying is smoothly continuous.

Brief description of the drawings

Fig. 1 is the result schematic diagram of virtual meter panel of the present invention;

Fig. 2 is dial plate Background of the present invention;

Fig. 3 is indicator structure of the present invention;

Fig. 4 is the simulation drawing of indicator of the present invention in processing procedure;

Fig. 5 is overall rasterizing figure of the present invention;

Fig. 6 is vertical grid of the present invention indicator after treatment;

Fig. 7 is that vertical grid of the present invention is processed first rectangle enlarged drawing;

Fig. 8 is horizontal grid of the present invention indicator after treatment.

Detailed description of the invention

For further understanding content of the present invention, Characteristic, hereby exemplify following examples, and coordinate accompanying drawing detailed Be described as follows:

Refer to Fig. 1 to Fig. 7, a kind of implementation method of pointer virtual meter panel, comprises the steps:

Step 101, set up a device context DC;

Step 102, loading dial plate background, and show on device context DC;

Step 103, copy two parts of memory context MEMDC1, MEMDC2, dial plate background is as painting canvas;

Step 104, loading indicator picture;

Step 105, obtain indicator image size, width w, length l, now indicator can represent to grow into l, wide is w's Rectangle;

Step 106, indicator pivot (X is set₀,Y₀)；

After step 107, indicator rotation alpha angle, with coordinate (X₀,Y₀) be pivot, carry out rasterizing place with step distance Reason, notices, device coordinate is generally the upper left corner;

Step 108, calculate by geometry, can draw as each little rectangular coordinates in Fig. 6 and Fig. 7;

Step 109, in memory context MEMDC1, draw the indicator of rotation alpha angle;

Step 110, the rectangular coordinates obtaining according to step 108, relevant position copying image in MEMDC1 is enterprising to DC Row shows;

Step 111, after angle [alpha] changes, in MEMDC1, repaint indicator, and calculate newly by geometry Rectangular coordinates;

Step 112, change according to angle [alpha] before rectangular coordinates, with upper one on respective background image wipe DC in MEMDC2 Inferior indicator displaying contents, keeps background constant;

Step 113, according to angle [alpha] change after rectangular coordinates, by relevant position copying image in MEMDC1 to DC enterprising Row shows;

If step 114 angle [alpha] changes, repeating step 111～113.

Further: the concrete computational process of above-mentioned steps 108 is as follows:

Step 1, known indicator image size, i.e. width w and length l, anglec of rotation α, step-length step;

Step 2, according to anglec of rotation α, known straight slope k=tan (α)

System coordinates is moved to indicator pivot (X by step 3.₀,Y₀) can try to achieve middle line function

y′＝k*x′

Wherein: x ' is the abscissa in translate coordinate system, y ' is the ordinate in translate coordinate system

Step 4, in the time of 0≤α≤45, according to picture width w, two long limits can obtaining other indicator rectangle frame are parallel Line function equation:

$y_{01}^{\&prime;}=k*x^{\&prime;}\underset{2*\cos \left(\mathrm{\&alpha;}\right)}{w}$

$y_{02}^{\&prime;}=k*x^{\&prime;}+\frac{w}{2*\cos \left(\mathrm{\&alpha;}\right)};$

Wherein: y '₀₁For the ordinate near x axial length limit, y '₀₂For the ordinate near y axial length limit.

Step 5, ask indicator image end points B0 point coordinates (x '_B0,y′_B0)

$x_{B0}^{\&prime;}=1*\cos \left(\mathrm{\&alpha;}\right)+\frac{w}{2}*\sin \left(\mathrm{\&alpha;}\right)$

$y_{B0}^{\&prime;}-1*\sin \left(\mathrm{\&alpha;}\right)-\frac{w}{2}*\cos \left(\mathrm{\&alpha;}\right)$

After step 6, vertical grid are processed, ask the grid coordinate that first rectangle (from right to left) upper left corner A0 orders (x "_A0, y″_A0)

$x_{A0}^{\&prime;\&prime;}=quotient\left(\frac{x_{B_0}^{\&prime;}}{step}\right)$

$y_{A0}^{\&prime;\&prime;}=quotient\left(\frac{y_{B_0}^{\&prime;}}{step}\right)-1$

Step 7, ask y '₀₂The coordinate of the intersection point C0 of extended line and first rectangle (x '_C0,y′_C0)

x′_C0＝(x″_A0+1)*step

$y_{C0}^{\&prime;}-k*x_{C0}^{\&prime;}+\frac{w}{2*\cos \left(\mathrm{\&alpha;}\right)}$

In step 8, grid coordinate, the grid coordinate of asking the lower right corner D0 of first rectangle to order

$x_{D0}^{\&prime;\&prime;}=quotient\left(\frac{x_{C_0}^{\&prime;}}{step}\right)=x_{A0}^{\&prime;\&prime;}+1$

$y_{D0}^{\&prime;\&prime;}=quotient\left(\frac{y_{C_0}^{\&prime;}}{step}\right)+1$

Step 9, the coordinate system of looking for novelty, i.e. linear equation in Grid Coordinate System

y″＝k*x″+c

Wherein: x " being the abscissa in Grid Coordinate System, y " is the ordinate in Grid Coordinate System

Will (x "_A0,y″_A0) substitution equation, try to achieve

c＝y″_A0-k*x″_A0

: y "=k*x " | y "_A0 k*x″_A0

Simplify: y "=k* (x "-x "_A0)+y″_A0

Step 10, will (x ", the processing of y ") discretization, n point coordinates is

x″_An＝x″_A0-n

y″_An＝y″_A0-quotient (k*n/0.99), 0.99 eliminates k conversion accuracy problem

Step 11, by α=45 substitution 4～10 steps, can obtain y direction grid limit quantity num, other anglecs of rotation Y direction grid quantity can not be greater than num, simplifies procedures operation time

num＝y″_D0-y″_A0

Step 12, calculate by above, draw first rectangular coordinates

Upper left corner coordinate: (x "_A0,y″_A0)

Lower right corner coordinate: (x "_D0，y″_D0)＝(x″_A0+1，y″_A0+num)

Step 13, other rectangular coordinates,

N rectangle upper left corner coordinate:

(x″_An，y″_An)＝(x″_A0-n，y″_A0-quotlent(k*n/0.99))

N rectangle lower right corner coordinate:

(x″_Dn，y″_Dn)＝(x″_An+1，y″_An+num)

Wherein n span: 0 < n≤x "_A0

Step 14, calculating above, be applicable to angular range (0≤α < 45), and as Fig. 6, indicator is near x axle, and rectangle frame is to erect length Shape is best, and (135≤α < 180), (180≤α < 225), (315≤α < 360) are also the same reasons; Other angle case, indicator Near y axle, rectangle frame is taking the wide shape of horizontal stroke as best, as Fig. 7.

Step 15, according to trigonometric function characteristic, can calculate the coordinate of all angular ranges, specific as follows:

(1) first quartile

Angular range (0≤α < 45)

The 1st rectangle (x "_A0，y″_A0)，(x″_D0，y″_D0)}

N rectangle (x "_An，y″_An)，(x″_Dn，y″_Dn)}

Angular range (45≤α < 90), α=90-α

The 1st rectangle (y "_A0，x″_A0)，(y″_D0，x″_D0)}

N rectangle (y "_An，x″_An)，(y″_Dn，x″_Dn)}

(2) the second quadrant

Angular range (90≤α < 135), α=α-90

The 1st rectangle (y "_D0，x″_A0)，(-y″_A0，x″_D0)}

N rectangle (y "_Dn，x″_An)，(-y″_An，x″_Dn)}

Angular range (135≤α < 180), α=180-α

The 1st rectangle (x "_D0，y″_A0)，(-x″_A0，y″_D0)}

N rectangle (x "_Dn，y″_An)，(-x″_An，y″_Dn)}

(3) third quadrant

Angular range (180≤α < 225), α=α-180

The 1st rectangle (x "_D0，-y″_D0)，(-x″_A0，-y″_A0)}

N rectangle (x "_Dn，-y″_Dn)，(-x″_An，-y″_An)}

Angular range (225≤α < 270), α=270-α

The 1st rectangle (y "_D0，-x″_D0)，(-y″_A0，-x″_A0)}

N rectangle (y "_Dn，-x″_Dn)，(-y″_An，-x″_An)}

(4) fourth quadrant

Angular range (270≤α < 315), α=α-270

The 1st rectangle (y "_A0，-x″_D0)，(y″_D0，-x″_A0)}

N rectangle (y "_An，-x″_Dn)，(y″_Dn，-x″_An)}

Angular range (315≤α < 360), α=360-α

The 1st rectangle (x "_A0，-y″_D0)，(x″_D0，-y″_A0)}

N rectangle (x "_An，-y″_Dn)，(x″_Dn，-y″_An)}

Step 16, above all quadrants coordinate are all with coordinate (X₀,Y₀) centered by, grid coordinate taking step as step-length, use In time, can revert to device coordinate or obtain device coordinate by grid matrix.

Above a kind of embodiment of invention is had been described in detail, but described content is only better enforcement of the present invention Example, can not be considered to for limiting practical range of the present invention. All equalizations of doing according to the present patent application scope change and improve Deng, within all should still belonging to patent covering scope of the present invention.

Claims (1)

1. an implementation method for pointer virtual meter panel, is characterized in that, comprises the steps:

Step 101, set up a device context DC;

Step 102, loading dial plate background, and show on device context DC;

Step 103, copy two parts of memory context MEMDC1, MEMDC2, dial plate background is as painting canvas;

Step 104, loading indicator picture;

Step 105, obtain indicator image size, width w, length l, now indicator can represent to grow into l, wide is the rectangle of w;

Step 106, indicator pivot (X is set₀,Y₀)；

After step 107, indicator rotation alpha angle, with coordinate (X₀,Y₀) be pivot, carry out rasterizing processing with step distance;

Step 108, calculate by geometry, obtain each little rectangular coordinates;

Step 109, in memory context MEMDC1, draw the indicator of rotation alpha angle;

Step 110, the rectangular coordinates obtaining according to step 108, arrive relevant position copying image in memory context MEMDC1 On device context DC, show;

Step 111, after angle [alpha] changes, in memory context MEMDC1, repaint indicator, and calculate by geometry Obtain new rectangular coordinates;

Step 112, change according to angle [alpha] before rectangular coordinates, with respective background image wipe equipment in memory context MEMDC2 Last indicator displaying contents on context DC, keeps background constant;

Step 113, rectangular coordinates after changing according to angle [alpha], by relevant position copying image in MEMDC1 to device context On DC, show;

If step 114 angle [alpha] changes, repeating step 111～113.